Please implement isvalidcc() and other functions which you may add to the c++ program.

Credit card numbers follow certain patterns. A credit card number must have between 13 and 16 digits. The starting numbers are: 4 for Visa cards, 5 for MasterCard cards, 37 for American Express cards, and 6 for Discover cards.

Example: Validating 4388576018402626

a) Double every second digit from right to left. If doubling of a digit results in a two-digit number, add the two digits to get a single digit number.

b) Now add all single-digit numbers from Step a:

4 + 4 + 8 + 2 + 3 + 1 + 7 + 8 = 37

c) Add all digits in the odd places from right to left in the card number:

6 + 6 + 0 + 8 + 0 + 7 + 8 + 3 = 38

d) Sum the results from Step b and Step c:

37 + 38 = 75

e) If the result from Step d is divisible by 10, the card number is valid; otherwise, it is invalid.

-DO NOT CHANGE THE MAIN METHOD

code-

bool isvalidcc(const string&);

int main()

{

//

// PLEASE DO NOT CHANGE main()

//

vector cardnumbers = {

"371449635398431", "4444444444444448", "4444424444444440", "4110144110144115",

"4114360123456785", "4061724061724061", "5500005555555559", "5115915115915118",

"5555555555555557", "6011016011016011", "372449635398431", "4444544444444448",

"4444434444444440", "4110145110144115", "4124360123456785", "4062724061724061",

"5501005555555559", "5125915115915118", "5556555555555557", "6011116011016011",

"372449635397431", "4444544444444448", "4444434444544440", "4110145110184115",

"4124360123457785", "4062724061724061", "5541005555555559", "5125115115915118",

"5556551555555557", "6011316011016011"

};

int i;

vector::iterator itr;

for (i = 1, itr = cardnumbers.begin(); itr != cardnumbers.end(); ++itr, i++) {

cout << setw(2) << i << " "

<< setw(17) << *itr

<< ((isvalidcc(*itr)) ? " is valid" : " is not valid") << endl;

}

return 0;

}